I'm not sure what happened, but I'm glad you're feeling better.
Were you constipated? If so, you should take psyllium husks, flax seeds (meal) or wheat bran, with a lot of water. If these don't work, a stool softener should solve the problem.
One question. You said egg whites... Make sure you keep your fat intake high -- Atkins is a high fat diet. Besides, most of the nutrients in eggs are in the yolks.